Is it OK to Place a Molly Fry in the Tank With a Filter Pump?

When a fish gives birth to live young, it is an amazing thing to witness. It is little wonder that people want to keep those little replicas alive and well. Choosing the right pump or opting out of a mechanical filter altogether can mean the difference between the life and death of our finned friends.

  1. Danger of Filters with Fry

    • Generally, it is not safe to place tiny fry (the young fish) in with a filter pump. The tiny, slow-moving fish can easily be sucked into the filter and killed very quickly. It is best to use either no filter or a sponge filter.

    Sponge Filters

    • Sponge filters work very well for cleaning the water of an aquarium. They have foam covers that prevent tiny fish and crustaceans from being drawn into the working parts of the pump.

    Non-filtered Tanks

    • Choosing to go without a filter is not unheard of, and molly fry will survive as long as the water is changed weekly. The best water to use when replacing old water is warm cycled aquarium water from a healthy fish tank.

    Using Plants for Filtration

    • Another alternative to mechanical filtration is to use a heavily planted tank. Plants will feed off the fish waste and cleanse the water efficiently. There is no chance of the fry being injured this way. This method makes it difficult to see the fry but offers them both protection from larger fish and plenty of food.

    When Molly Fry are Big Enough for Filters

    • After they have more than doubled in size, the fry should be strong enough swimmers to avoid being sucked up into a filter pump. They can also be placed in with other fish at this stage.